Japanese patent application published under the number 1-173 501 discloses a headlight in which a spirit level is used to indicate the direction in which the reflector is pointing relative to the horizontal for the purpose of performing elevation adjustment on the beam. The spirit level is mounted on a body capable of being removably disposed on the rear of the lamp base when the lamp is mounted in the reflector.
A drawback of this device lies in that the accuracy with which it indicates headlight direction depends on the accuracy with which the lamp is positioned in the hole for the lamp in the reflector. Thus, in the conventional case where very large clearance may exist between the reflector and the lamp, or where positioning reproducibility from one lamp to another is poor, particularly because of the manufacturing tolerances on lamp bases, the indication given is not of sufficient accuracy.
The present invention seeks to mitigate this drawback.